The sales volume of the next month is predicted by the data in the past. The sales volume is changed greatly from month to month, but the annual fluctuation pattern is almost the same every year. Which of the following is the most appropriate formula that can be used for calculating the sales volume of the next month? Here, Pt+1 is the sales volume predicted for the next month, St is the sales volume of the current month t, and the data is retained for three years.
a) Pt+1 = (St+ St–1+ St–2) / 3
b) Pt+1= St xSt / St–1
c) Pt+1= (St+ St–12 + St–24) / 3
d) Pt+1= (St–11+ St–23+ St–35) / 3
I would love to know the right method to solve this one, some explanations will be greatly appreciated!